What foam compression factor is advised for AP900 case?

Joe Zeglinski


I saw a post on the AP-ug group, where someone is using 90 lb/sq. inch
"closed cell ethafoam" as a lining for their AP mount. I have read that the
"foam dice" in typical cases, like the Pelican, get chewed up after a while,
and require a replacement - which costs a couple of hundred dollars US, or

So, what foam compression PSI factor is recommended by Astro Physics, for
a travel case, based on the weight of the AP900 (complete, or in parts) - and
possibly for the AP1200, as well?

This has to do with how much deceleration can be tolerated by the mount,
in normal travelling, or worse, in the average toss or drop by the airport
gorilla baggage handlers?

Perhaps, as a guide, what is the PSI of the "hard" ethafoam that our newly
purchased AP900 or AP1200 come packaged in? I assume, AP has calculated the
tolerable damage risk of it's initial shipment to us, in their selection of
the hard foam, used in the cardboard boxes.

This information will be of great help in specifying the correct foam to
purchase for my new AP900 case, or more likely two cases. I assume this advice
would be based on the weight of just the RA and/or DEC assemblies (the manner
in which it is shipped to us), because one can't know if the counterweights
and shaft would travel separately, and if the hand controller were in either
one. The hand controller is already protected by the new rubber casing, so I
assume a one metre drop to a paved driveway, is survivable.

Certainly, a well considered recommendation, or a white paper by Roland, would


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